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| Looking north toward Antelope Valley over the burned landscape south of Walker, spring 2006. |
We were at the bottom of a steep hill, so we couldn't see how close the fire was on the other side. We just knew it was coming. This was my first big wildfire as a volunteer on the Lee Vining Volunteer Fire Department, and I wasn't exactly sure what to expect. It was nerve wracking, waiting and knowing nothing except the direction the fire was coming from--and that it was expected to arrive soon.
Then, suddenly, we got a call on the radio to hurry to another part of town where the wildfire was already arriving. We raced down the canyon--away from the houses that perhaps would have been luckier had the fire arrived while we were there--and raced around the hill to the north, where the fire was funneling through a gap in the hill toward town. We backed the fire truck up the driveway of a house that was right at the bottom of the gap, and got the hoses out into the backyard and started pumping water--spraying down the house and the propane tank and nearby brush, but mostly conserving water and waiting and watching the fire move closer. The defensible space was very good--just a relatively barren yard with sagebrush on the far side. But the steep hillside was right on the other side of the open yard, and the fire was slowly moving down the hill.
We started feeling the heat, and pretty soon a pinyon pine about 100 feet away caught fire. It quickly became a fireball, and we wetted things down more while trying to withstand the rapidly increasing heat. But within a minute or two the heat became unbearable, and we stopped pumping water and jumped on the back of the fire truck as it drove down the driveway, hoses trailing behind it, pursued by air filled with smoke and glowing embers.
I think that house still stands. We went to a hydrant to refill our truck's water tank, and then we were tasked with waiting for the fire to arrive at a house high on a hill on the other side of the river. We had excellent views of the fire progress and the aerial attack. We watched the fire cross Walker Canyon and then barrel up the pinyon-covered east slope like a volcano. We watched a C-130, on one of its retardant drops, begin to pull up at the bottom of the hill but only the wings went up--the fuselage kept going down and crashed into the ground in an incredible explosion. In disbelief, we ended our waiting game and jumped in our engines and raced down to town--for the second time that day--and fought the grass and brush fire created by the explosion of aviation fuel, directly attacking it in near-zero visibility (and breathability) as it moved toward us behind the homes and businesses along the east side of Hwy 395. The water tender on our strike team never made it--it rolled as it raced around a curve, going too fast amidst the excitement and horror of the plane crash. The lives lost that day were all firefighters.
Most of the heat that drove us out of the backyard that morning was created by the burning of just one pinyon pine. And there was no wind. If I had to do it over again, I would have trained my hose on the pinyon pine before it ignited. It might have ignited anyway, but I think that would have been the most effective use of our time and water. I suspect any water that we had sprayed on the propane tank evaporated pretty quickly when it got hot, making little difference. The painted wood siding on the back of the house probably shed the water and evaporated it almost as quickly, meaning dousing it before the fire arrived made little difference once the fire got hot. But if that pinyon pine hadn't gone up in flames, the heat level would have been considerably lower, and we would have been able to make a stand in the backyard, staying behind, capable of actually fighting the fire if the structure had ignited.
Following this month's fires in Sonoma County, especially the Tubbs Fire in Santa Rosa and this video by the Berkeley Fire Department and this one of the wind-driven embers, I've been thinking about other ways to fight a fire.
My sister-in-law's house in Healdsburg was about 100 yards away from the edge of one of the fires. She had neighbors that lost homes and barns. As one of the barns burned, a fire truck had stopped, but was out of water from fighting another fire over the hill.
Instead of using water--which is heavy, in limited supply, and evaporates in the heat--what about using air?
I'm thinking about those huge fans that make the fake wind in movies. Maybe even something bigger. And perhaps a wind-break, like a water-filled semi truck with fireproof sides and heat shields extending to the ground and above it. Where one side of a street is burning and the other is not, you could drive one or several of these semis down the street, blocking the wind-driven embers. Perhaps at the edge of the fire the big industrial movie-fan could blow it back onto itself, keeping it from spreading in that direction.
While intriguing, I must conclude that these are bad ideas--if they worked, and were widely used, they would be like levees promoting development in dangerous floodplains, and directing worse flooding into your neighbors. Firebreaks also give a false sense of security--when you think about fires that jump six-lane freeways. You can stop many floods with levees and dams, and you can stop many fires with roads or firebreaks, but you can't stop the biggest ones. There will always be an unstoppable flood or fire, and it could be argued that levees/dams and firebreaks make those losses greater by promoting development in dangerous areas. If money spent on those measures were instead used to move development out of dangerous areas, long-term losses would be reduced. We don't need quick, clever technological fixes--we need smarter development.
And we need reporters to stop saying that wildlands are "destroyed" by fire. "Consumed" is maybe ok, but fire is a natural disturbance process and they tend not to destroy anything for long except what people build. I recently read something saying that a fire decades ago destroyed most of the Mendocino National Forest. Uh... it is still there. Nothing was destroyed but a temporary stage of ecological succession.
But what about the already-developed wildland-urban interface? What can we learn that can reduce losses of life and property?
If you look at Marin County, and many other areas, you notice grassy south or west-facing slopes and forested north or east-facing slopes. Geology, soils, and fire history work together to make this mosaic of habitats. But fire history might be responsible for more of this pattern than we realize. I hadn't thought about this before, but the south and west-facing slopes are also where warm and dry downslope winds develop in the fall. The north and east-facing slopes experience downslope winds that recently came off the ocean, and are cooler and more humid. Sure, NE slopes are cooler and more humid anyway, but I wonder what comparing the wind history of a weather station on these different slopes would show--if you looked at maximum wind speed for a given direction at the drier times of year, would there be an obviously greater magnitude downslope peak wind speed on the grassy slopes?
With this in mind, I would think that the south and west-facing grassy slopes might be more dangerous places to build. Not that building in forests is any safer--but the pros and cons of each are worth considering. Grass fires move faster, but are more easily put out. And blowing embers make the nearby vegetation less important, and a fireproof structure all-important.
Speaking of building in forests, what about redwood forests? Well, they seem fireproof, but they burn too. Last weekend we had a campfire in a redwood forest, and tried burning green leaves that we gathered. Everything green burned--bay, ash, hazelnut, ferns, even redwood leaves and thin redwood bark. Now, the thick bark is obviously quite fireproof, however the fire scars on old trees show how much good that will do when subjected to enough heat for long enough.
Now, I love pinyon pines. But I'd want them at least 100 feet away from my house. Or, to state it in more smart development terms, I'd want my house to be built at least 100 feet away from a pinyon woodland. Unless it was an underground house.
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